As remedies of diabetes, various biguanide compounds and sulfonylurea compounds have so far been used. However, biguanide compounds are hardly used at present, since they cause lactic acidosis, while sulfonylurea compounds, which have a strong action of lowering blood sugar, often cause severe hypoglycemia, requiring special attention in use. On the other hand, there are thiazolidinedione derivatives and oxazolidinedione derivatives known to have actions of lowering blood sugar and lipid in blood, which are free of such drawbacks.
For example, JPA H3(1991)-170478 and WO9202520-A1 describe, as 2,4-oxazolidinedione derivatives having substituents at the 5-position, a series of 5-(substituted benzyl)-2,4-oxazolidinedione derivatives, JPB S62(1987)-30993 describes 2,4-oxazolidinedione derivatives substituted with an alicyclic hydrocarbon group at the 5-position, and JPB S63(1988)-35632 describes 2,4-oxazolidinedione derivative substituted with, among others, a substituted aromatic ring at the 5-position.